U.S. patent number 5,571,325 [Application Number 08/476,052] was granted by the patent office on 1996-11-05 for subtrate processing apparatus and device for and method of exchanging substrate in substrate processing apparatus.
This patent grant is currently assigned to Dainippon Screen Mfg. Co., Ltd.. Invention is credited to Hideki Adachi, Yoshio Matsumura, Yasuhide Tanaka, Tsutomu Ueyama.
United States Patent |
5,571,325 |
Ueyama , et al. |
November 5, 1996 |
Subtrate processing apparatus and device for and method of
exchanging substrate in substrate processing apparatus
Abstract
A substrate processing apparatus comprises a processing part and
a transferring part. In the processing part there are a plurality
of stages in which a plurality of processing units are arranged in
a row along a horizontal direction and the stages are arranged in a
stack vertically. Thus, the processing units are arranged in
matrix. The transferring part includes a plurality of horizontal
transferring devices each movable in the horizontal direction and a
vertical transferring device movable in the vertical direction.
Hence, a substrate is movable both horizontally and vertically to
be transferred to the desired processing unit.
Inventors: |
Ueyama; Tsutomu (Kyoto,
JP), Adachi; Hideki (Kyoto, JP), Matsumura;
Yoshio (Hikone, JP), Tanaka; Yasuhide (Kyoto,
JP) |
Assignee: |
Dainippon Screen Mfg. Co., Ltd.
(JP)
|
Family
ID: |
26480496 |
Appl.
No.: |
08/476,052 |
Filed: |
June 7, 1995 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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170094 |
Dec 20, 1993 |
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Foreign Application Priority Data
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Dec 21, 1992 [JP] |
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4-356752 |
May 27, 1993 [JP] |
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5-151160 |
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Current U.S.
Class: |
118/320; 414/940;
414/217; 414/935; 414/936 |
Current CPC
Class: |
H01L
21/67751 (20130101); G03F 7/7075 (20130101); H01L
21/67178 (20130101); H01L 21/68707 (20130101); H01L
21/67161 (20130101); H01L 21/67748 (20130101); G03F
7/70733 (20130101); H01L 21/67742 (20130101); Y10S
414/14 (20130101); Y10S 414/135 (20130101); Y10S
414/136 (20130101) |
Current International
Class: |
H01L
21/00 (20060101); H01L 21/67 (20060101); H01L
21/677 (20060101); G03F 7/20 (20060101); B05C
013/02 () |
Field of
Search: |
;118/320,319
;414/935,939,222,217,609,DIG.1,DIG.2,DIG.6,3-5 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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63-5523 |
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Jan 1988 |
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JP |
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282522A |
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Mar 1990 |
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JP |
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282618A |
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Mar 1990 |
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JP |
|
Primary Examiner: Housel; James C.
Assistant Examiner: Freed; Rachel
Attorney, Agent or Firm: Ostrolenk, Faber, Gerb &
Soffen
Parent Case Text
This is a continuation of application Ser. No. 08/170,094 filed on
Dec. 20, 1993, now abandoned.
Claims
We claim:
1. A substrate processing apparatus for transferring and processing
substrates having plate configurations, said apparatus
comprising:
processing means including a plurality of processing units for
processing each of said substrates serially one by one, each of
said processing units processing said substrates in a selected one
of a plurality of different manners, each of said processing units
including a holding component for holding each of said substrates
horizontally while said substrate is processed in said processing
unit, said processing units being arranged in upper and lower
processing rows, each processing row comprises selected ones of
said plurality of said processing units arranged in a predetermined
horizontal direction, said upper processing row being arranged
above and in parallel with said lower processing row; and
transferring means, arranged along both said upper and lower
processing rows, for transporting each of said substrates, one by
one in a predetermined order, while simultaneously supporting each
of said substrates horizontally, to each of said processing units,
said transferring means also receiving each of said substrates from
said holding component of each of said plurality of processing
units and transferring said substrate to said holding component of
another one of said processing units.
2. A substrate processing apparatus of claim 1, wherein said
transferring means includes a horizontally movable component for
transferring said substrate in a horizontal direction along said
upper and lower processing rows, and a vertically movable component
for transferring said substrate in a vertical direction between
said upper and lower processing rows.
3. A substrate processing apparatus of claim 1, further comprising
means for supplying clean air downwardly to said transferring
means.
4. A substrate processing apparatus of claim 1, wherein at least
one of said processing units in said upper processing row includes
a plurality of processing components each of which processes one of
said plurality of substrates in an identical manner, said plurality
of processing components being arranged vertically with respect to
each other.
5. A substrate processing apparatus of claim 1, wherein at least
one of said processing units in said lower processing row includes
means for processing said substrates individually one by one while
each of said substrates rotates around a vertical axis
perpendicular to said substrate.
6. A substrate processing apparatus of claim 1, wherein at least
one of said processing units in said upper processing row includes
means for processing substrates individually one by one without
rotating said substrates.
7. A substrate processing apparatus of claim 6, wherein at least
one of said processing units in said upper processing row includes
means for heating said substrate.
8. A substrate processing apparatus of claim 6, wherein at least
one of said processing units in said upper processing row includes
means for cooling said substrate.
9. A substrate processing apparatus of claim 6, wherein at least
one of said processing units in said upper processing row includes
means for coating said substrate with an adhesion agent.
10. A substrate processing apparatus of claim 5, wherein at least
one of said processing units in said lower processing row includes
means for coating a photo-resist liquid on said substrate while
said substrate rotates and while said photo-resist liquid is on
said substrate.
11. A substrate processing apparatus of claim 5, wherein at least
one of said processing units in said lower processing row includes
means for supplying developing liquid on said substrate while said
substrate rotates.
12. A substrate processing apparatus of claim 1, wherein said
substrate to be processed is generally rectangular.
13. A substrate processing apparatus of claim 12, wherein said
substrate to be processed is a glass substrate used for
manufacturing a liquid crystal display.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is directed to a substrate processing
apparatus for processing a substrate in a plurality of processing
units in a predetermined order by transferring the substrate
between said plurality of processing units. The present invention
is also directed to a device for and a method of transferring
substrates in the substrate processing apparatus by removing a
processed substrate from a processing unit and by inserting a
substrate to be processed to the processing unit, such as a resist
coating device, substrate cleaning device, substrate developing
device, substrate heating device, substrate cooling device,
exposing device and so on.
2. Description of the Background Art
In manufacturing fine electronic substrates such as liquid crystal
displays and semiconductor devices, it is necessary to have a
plurality of processing units described above and a transferring
device, which transfers substrates such as glass substrates for
liquid crystal displays or semiconductor wafers to the plurality of
processing units in a predetermined order.
In one prior art apparatus, all of the plurality of processing
units are arranged in a horizontal row on a floor. However, this
arrangement of processing units causes an increase of the floor
area required for the apparatus by increasing total length of the
apparatus, since many processing units are necessary for
manufacturing fine electronic substrates such as liquid crystal
displays and semiconductor devices. This arrangement has the
further disadvantage of being difficult to modify, from a
predetermined order, the order of processing units in which a
substrate is processed, since the substrate transferring device of
this arrangement is designed to transfer a substrate in a
predetermined order in a specified direction. It is difficult to
change such predetermined order and/or such specified direction.
That is, for transferring the substrate in a different order from
said predetermined order, the substrate must be transferred in the
opposite direction to said specified direction or must bypass a
specified processing unit. This transferring causes interference
between a plurality of substrates transferred in series.
U.S. Pat. No. 4,985,722 discloses a second prior art apparatus in
which a plurality of processing units are arranged in two laterally
spaced horizontal rows spaced in parallel with each other, and a
substrate transferring device is positioned in the space formed
between the two horizontal rows. In this second prior art
apparatus, it is easy to modify, from a predetermined order, the
order of those processing units in which a substrate is processed,
because such modification is achieved by a change of action of the
substrate transferring device without modification of arrangement
of the processing units. The total length of the apparatus of the
second prior art apparatus is shorter than that of the first prior
art, since the plurality of processing units are arranged in two
horizontal rows. However, the floor area required for operating the
apparatus of the second prior art is not reduced in comparison with
that of the first prior art, since the apparatus of the second
prior art is different from that of the first prior art only in the
arrangement of the plurality of processing units.
Furthermore, in the second prior art apparatus, the check and/or
repair of the substrate transferring device is difficult, since it
is positioned between the two horizontal rows. The second prior art
apparatus has the further disadvantage that the time required for
exchanging substrates in a processing unit increases. That is, in
the second prior art apparatus, a processed substrate is taken out
of a processing unit, and a next substrate, which has not been
processed in that processing unit, is taken into the processing
unit thereafter.
Japanese Laid-Open Patent Application No. Sho63-5523 discloses a
third prior art apparatus in which a plurality of processing units
are arranged vertically one by one and a substrate is transferred
only in the vertical direction.
This arrangement embodied in the third prior art apparatus can
reduce the floor area required for the apparatus in comparison with
apparatus of the first and second prior arts. However, the height
of the third apparatus increases, especially for apparatus
including a large number of processing units. Therefore, in the
third prior art apparatus, the number of processing units included
in the apparatus must be limited by the ceiling height of factory
in which the apparatus is to be installed. In the arrangement
disclosed in the third prior art it is also inconvenient to check
and/or repair a processing unit arranged at or near the top of the
apparatus.
Because some of the processing units included in this type of
apparatus are heavy and/or require many pipes for supplying a
plurality of different treating liquids, such processing units
should not be arranged at relatively high locations. Therefore, the
arrangement disclosed by the third prior art is a poor design
choice. Similar to the first prior art apparatus, this third
apparatus has the further disadvantage that it is difficult to
modify, from a predetermined order, the order of those processing
units in which a substrate is processed. In the third prior art
apparatus, the substrate transferring device, for transferring the
substrate between the plurality of processing units, transfers the
substrate vertically by relatively long distances. The particles
generated by such transference of the substrate settle on the
processing units disposed at relatively low positions, causing
contamination of such processing units and substrates thereat. The
substrate transferring device used in the third prior art apparatus
must transfer a large number of substrates only in a vertical
direction, many of the transferring paths necessary for
transferring substrates from a specified processing unit to the
next specified processing unit, must be designed for avoiding
interference between all of the transferring paths. This serves to
increase the time required for processing a substrate in all of the
processing units in a predetermined order.
SUMMARY OF THE INVENTION
The present invention is directed to a substrate processing
apparatus for processing a substrate by a plurality of processing
units by transferring the substrate between the plurality of
processing units in series, each of the processing units processing
the substrate in a predetermined manner. This apparatus comprises a
processing section including a lower processing row wherein some of
the plurality of processing units are arranged in a predetermined
horizontal direction, and an upper processing row wherein others of
the plurality of processing units are arranged in the predetermined
horizontal direction, the upper processing row being arranged above
the lower processing row in parallel with the latter. Transferring
means, arranged along both of the upper and lower processing rows,
are provided for transferring the substrate in both the horizontal
and vertical directions from a predetermined one of the plurality
of processing units in both of the upper and lower processing rows
to another one thereof.
The present invention is also directed to a device for exchanging
substrate in substrate processing apparatus that includes a
plurality of processing units. The device comprises upper and lower
substrate holding mechanisms, provided in each of the processing
units, for holding respectively thereon a processed substrate which
has been processed in the processing unit and a next substrate
which is to be processed next in the processing unit; upper and
lower hands, moveable into and out of each of the processing units,
for taking the processed substrate out of a specified processing
unit and taking the next substrate into the specified processing
unit, the vertical space between the upper and lower hands being
variable; space controlling means for controlling the vertical
distance between the upper and lower hands, to transfer the
processed substrate held on either of the upper and lower substrate
holding mechanisms to either of the upper and lower hands, and to
transfer the next substrate held on either of the upper and lower
hands to either of the upper and lower substrate holding
mechanisms; and means for controlling the movement of the upper and
lower hands, to transfer the processed substrate from the
processing unit to the other processing unit and to transfer the
next substrate to the processing unit.
The present invention is further directed to a method of exchanging
substrates in substrate processing apparatus that includes a
processing unit, upper and lower substrate holding mechanisms
provided in the processing unit for holding respectively thereon a
processed substrate which has been processed in the processing unit
and a next substrate which is to be processed next in the
processing unit, and upper and lower hands, movable into and out of
the processing units, for taking the processed substrate out of the
processing unit and taking the next substrate into the processing
unit, with the vertical space between the upper and lower hands
being variable. The method comprises the steps of: (a) holding the
processed substrate on the upper substrate holding mechanism in the
processing unit and holding the next substrate by the lower hand
located outside of the processing unit; (b) inserting the upper and
lower hands into the processing unit with the next substrate being
held by the lower hand; (c) simultaneously moving the upper hand
upwardly to receive the processed substrate held on the upper
substrate holding mechanism, and moving the lower hand downwardly
to transfer the next substrate held thereby to the lower substrate
holding mechanism; and (d) removing the upper and lower hands from
the processing unit with the processed substrate being held by the
upper hand.
In another aspect of the present invention, the method comprises
the steps of: (a) holding the processed substrate on the lower
substrate holding mechanism in the processing unit and holding the
next substrate by the upper hand located outside of the processing
unit; (b) inserting the upper and lower hands into the processing
unit with the next substrate being held by the upper hand; (c)
simultaneously moving the lower hand upwardly to receive the
processed substrate held on the lower substrate holding mechanism,
and moving the upper hand downwardly to transfer the next substrate
held thereby to the upper substrate holding mechanism; and (d)
removing the upper and lower hands from the processing unit with
the processed substrate being held by the lower hand.
Accordingly, an object of the present invention is to provide a
substrate processing apparatus in which an order of processing a
substrate can be modified easily.
Another object of the present invention is to provide a substrate
processing apparatus which is compact in size.
Still another object of the present invention is to provide a
substrate processing apparatus in which it is easy to check and/or
repair substrate a transferring device for transferring a substrate
between a plurality of processing units in the apparatus.
Yet another object of the present invention is to provide a
substrate processing apparatus which decreases the time required
for processing a substrate in all of the processing units in a
predetermined order.
A further object of the present invention is to provide a substrate
transferring apparatus combined in substrate processing apparatus,
which can avoid contamination often caused by operation of prior
art transferring apparatus to substrates to be processed and
processing units.
A still further object of the present invention is to provide a
device for and method of exchanging substrates in substrate
processing apparatus, which operates efficiently to take a
substrate into each of the processing units and remove a substrate
processed by each of processing units from the processing unit.
These and other objects, features, aspects and advantages of the
present invention will become more apparent from a study of the
following detailed description of the present invention when taken
in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of an embodiment of a substrate processing
apparatus according to the present invention;
FIG. 2 is a schematic arrangement of the first sub-system in the
embodiment of FIG. 1;
FIG. 3 is a side view looking in the (-X) direction along line
III--III of FIG. 2;
FIG. 4 is a schematic arrangement of the second sub-system in the
embodiment;
FIG. 5 is a side view looking in the (-X) direction along line V--V
of FIG. 4;
FIG. 6 is a diagrammatic perspective view of the handler;
FIGS. 7A, 7B and 7C are schematics illustrating the operation of
the substrate transferring device;
FIG. 8 is a perspective showing flow of a substrate in the first
sub-system;
FIG. 9 is a perspective showing flow of a substrate in the second
sub-system;
FIG. 10 is a perspective of a substrate processing apparatus
including a substrate exchanging device constructed according to
the present invention;
FIG. 11 is a side view looking in the (-X) direction along line
XI-XI of FIG. 10;
FIG. 12 is a perspective of the substrate transferring device of
FIG. 11;
FIG. 13 is a side elevation of the substrate transferring device
looking in the direction of the arrow VII in FIG. 12;
FIG. 14 is a plan view of the substrate transferring device looking
in the direction of the arrow VIII in FIG. 12;
FIG. 15 is a front elevation of the substrate transferring device
looking in the direction of the arrow IX in FIG. 12;
FIG. 16 is a sectional plan view of a space controlling mechanism
taken in the (-Z) direction;
FIG. 17 is a front view of the space controlling mechanism taken in
the (+Y) direction, with portions broken away for the sake of
clarity;
FIG. 18 is a detail view of portions connected between an arm in
FIG. 16 and a body;
FIGS. 19A to 19D and 20A to 20D are schematics showing the
operation of exchanging a processed substrate for another
substrate;
FIG. 21 is a perspective of an embodiment of a substrate holding
mechanisms in a spin coating device;
FIG. 22 is a perspective of an embodiment of a substrate holding
mechanisms in hot hot plate;
FIG. 23 is an internal side view of the hot plate in FIG. 22;
FIG. 24 is a plan view of a link mechanism which connects between
upper levers;
FIG. 25 is an internal front view of the hot plate;
FIG. 26 is a timing chart illustrating the first operation of the
substrate transferring device and the hot plate, assuming that the
processed substrate is put on claws of the upper levers while the
next substrate is put on claws of lower levers;
FIG. 27 is a timing chart illustrating the second operation of the
substrate transferring device and the hot plate, assuming that the
processed substrate is put on the claws of the lower levers while
the next substrate is put on the claws of the upper levers, in
reverse;
FIG. 28 is an elevation showing a modification of the hot plate;
and
FIG. 29 is a perspective showing a hand in the modification of the
hot plate.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A. Substrate Processing Apparatus
<A-1. Overall Structure of the Apparatus>
The substrate processing apparatus 1 of FIG. 1 functions as an
apparatus for forming patterns of electrodes or the like on a
substrate to be processed, such as a liquid crystal display
substrate.
In FIG. 1 and the following drawings, symbols (.+-.X) and (.+-.Y)
represent the directions, parallel to a floor, which orthogonally
intersect with each other in the floor plane, and symbols (.+-.Z)
represent the vertical directions which orthogonally intersect with
these directions (.+-.X) and (.+-.Y). Thus, these directions define
a three dimensional rectangular coordinate system. Furthermore,
symbol X represents the (+X) and/or (-X) direction, and symbol Y
and Z represent the corresponding directions, similarly.
As shown in FIG. 1, the apparatus 1 has a substantially inverted
C-shape and comprises a processing system 20 which includes first
and second sub-systems A and B disposed in parallel to each other
and back to back. There is a space 9 between the first and second
sub-systems A and B. The first sub-system A is to provide a
preliminary treatment to a substrate 10 having a resist film prior
to an exposing process while the second sub-system B is to provide
a post-treatment to the exposed substrate 10, both of the
sub-systems A and B extending in the X direction.
A substrate loading station 2 is connected to one end portion of
the first sub-system A which is in the (-X) direction side. A
plurality of substrates 10 rinsed with pure water are stored with a
cassette 3, and thereafter the cassette 3 storing the substrates 10
is carried into the substrate loading station 2. In the station 2,
each substrate 10 is taken out of the cassette 3 and transferred
into the first sub-system A by a substrate transferring robot 4a
operable to move in the X direction (indicated by a dashed
arrow).
The first sub-system A comprises a processing part A1 and a
horizontal transferring part A2. The processing part A1 performs
predetermined processes to the substrate 10 and transfers the
substrate 10 in the vertical direction. The horizontal transferring
part A2 transfers the substrate 10 along a row of the processing
part A1, i.e. in the X direction. The processing part A1 is faced
to the space 9 while the horizontal transferring part A2 is
arranged in the opposite side of the space 9 across the processing
part A1.
The first sub-system A has a specific structure to perform the
preliminary treatment to the substrate 10, so that photo-resist is
coated on the surface of the substrate 10. The structure of and the
treatment in the first sub-system A will be explained later.
The substrate 10, subjected to processing in the first sub-system
A, is transferred into a buffer 6 extending in the Y direction
between the first and second sub-stations A and B. An exposing
machine, i.e. step-and-repeat machine 5 stands by the buffer 6.
A robot 6a is provided in the buffer 6 to hold each substrate 10
over the exposing machine 5 which transfers patterns onto the
resist film using a predetermined mask. The exposed substrate 10 is
returned to the buffer 6 and then carried into a supplementary
exposing part 7 by another robot 6b. The supplementary exposing
part 7 includes an edge exposing machine and a character printing
machine, so that the resist film on the substrate 10 is subjected
to edge exposing as well as character printing. Upon completion of
the edge exposing and the character printing, the substrate 10 is
transferred to the second sub-system B.
Similarly, the second sub-system B has a processing part B1 and a
horizontal transferring part B2. The parts A1 and B1 stand back to
back so as to sandwich the space 9. The horizontal transferring
part B2 stands adjacent processing part B1 on the side thereof,
opposite of the space 9.
The structure and the operation of the second sub-system B2 will
also be explained later. Upon completion of processing in the
second sub-system B, the resist film has been developed. Each
substrate 10 having the developed resist film is carried into
unloading station 8 and then stored with the cassette 3 by a robot
4b movable in the Y direction.
The cassette 3 storing the processed substrates 10 is transferred
from the unloading station 8 to the next processing station.
<A-2. Structure of First Sub-system A>
FIG. 2 is a schematic arrangement view of the first sub-system A
and FIG. 3 is a side structure view taken in the (-X) direction
along line III--III of FIG. 2.
In the sub-system A seen best in FIGS. 2 and 3, a plurality of
processing units are arranged in a two dimensional matrix so that
first and second stages AF1 and AF2 are stacked in the Z direction.
The first stage AF1 of the processing part A1 comprises a spin
scrubbing device SS, a spin coating device SC and a rinsing part ER
for removing unnecessary resist film formed on the edge and back
portions of the substrate 10 which are disposed in the X direction.
Elevators EL1 and EL2 are provided between the first and second
stages AF1 and AF2 and go up and down in the Z direction as
indicated by a dashed double arrow.
The horizontal transferring part A2 is located in the front side of
the processing part A1, i.e. in the (-Y) side. The horizontal
transferring part A2 includes a floor 41, extending in the X
direction, on which a guide rail 43 is secured. Two handlers 30a
and 30b are mounted on the guide rail 43, so as to be operable to
travel in the X direction along the guide rail 43. The handlers 30a
and 30b function as substrate transferring means for transferring
the substrate 10 among the processing units. The structure of the
handlers 30a and 30b will be explain later.
The second stage AF2 is positioned above the first stage AF1. The
second stage AF2 has a two-layer structure, in which a first layer
is formed by hot plates (oven) HP1, HP4 and HP5 and cool plates CP1
to CP3 arranged in the X direction. A second layer is formed by hot
plates HP2, HP3 and HP6. As shown in FIG. 3, the corresponding
processing units (for example, the cool plate CP1 and the hot plate
HP3) are stacked up in the Z direction. Openings D1 and D2 are
opened at portions of the second layer, the portions being just
above the upper portions of the elevators EL1 and EL2. Thus, the
elevators EL1 and EL2 can move between the stages AF1 and AF2
through the openings D1 and D2.
Similarly, in the second stage AF2, a horizontal transferring part
is present in the front side of processing part A1. The horizontal
transferring part includes a floor 42 extending in the X direction.
A guide rail 43 extending in the X direction is fixed on the floor
42. Two handlers 30c and 30d are mounted on the guide rail 43, so
as to move in the X direction along guide rail 43.
Each of the processing parts SS, SC, ER, HP1 to HP6 and CP1 to CP3
corresponds to the "processing unit" according to the present
invention. The processing units SS, SC and ER are disposed in a row
in the first stage AF1 to form in a row while the processing units
HP1 to HP6 and CP1 to CP3 are disposed in the second stage AF2 to
form in a row, so that multi-stage type processing rows are
structured. It is understood from FIG. 2 that a single layer of the
processing units is formed in the first stage AF1 while two layers
of the processing units are formed in the second stage AF2. Thus,
the first sub-system A has a two-stages and three-layers structure
of the processing units.
Referring to FIG. 3, a filter 42f is disposed between a ceiling
surface of the first stage AF1 and the floor 42 of the second stage
AF2. Clean air F flows from the ceiling surface of the first stage
AF1 through the filter 42f toward the floor 41 as well as from the
ceiling surface of the second stage AF2 through a filter 44f toward
the floor 42. Thus, the "down flow" of the clean air is partially
formed in the respective first and second stages AF1 and AF2.
Furthermore, a filter 45f is disposed on a ceiling surface above
the devices provided in the processing part A1 so that clean air
flow downwardly through the filter 45f toward the devices.
The local down flows F prevent down flow RF, applying to the whole
apparatus, from being disturbed by movement of the handler 30a to
30d, and carry particles generated in each stage away from the
substrate and the processing units. The floor 42 also prevents
particles generated in the second stage AF2 from moving to the
first stage AF1. The down flow may be downwardly formed across the
moving path of the handlers 30a to 30d obliquely.
<A-3. Structure of Second Sub-system B>
FIG. 4 is a schematic arrangement view of the second sub-system B
and FIG. 5 is a side structure view taken in the (-X) direction
along line V--V of FIG. 4.
Similarly, the second sub-system B has a two-stages and
three-layers structure of the processing units. The processing part
B1 comprises two spin developing devices SD1 and SD2 which are
disposed in the X direction. Elevators EL3 and EL4 are provided so
as to sandwich the spin developing devices SD1 and SD2.
In the front side of the processing part B1, i.e. in the (+Y) side,
a horizontal transferring part B2 is arranged. The horizontal
transferring part B2 has a floor 51 on which a guide rail 53 is
secured. A handler 30e is mounted on the guide rail 53, and moves
in the X direction along the guide rail 53 to transfer the
substrates among a first stage BF1.
Second stage BF2 has a two-layers structure of the processing
units. A first layer of the second stage BF2 includes hot plates
HP7 to HP9 and a cool plate CP4 which are disposed in a row, and
has openings D3 and D4 through which the elevators EL3 and EL4 move
in the Z direction. A second layer of the second stage BF2 includes
a hot plate HP10.
The second stage BF2 includes a horizontal transferring part
extending in the X direction which is arranged in the front side of
the processing part, i.e., in the (+Y) side. A handler 30f is
mounted on a guide rail 53 which is secured on the floor 52, to
move in the X direction. Thus, the substrate is transferred in the
second stage BF2 by means of the handler 30f.
Referring to FIG. 5, filters 52f, 54f and 55f are attached on the
respective ceiling surfaces 52, 54 and 55 in the stages. Clean air
flows downwardly through these filters 52f, 54f and 55f, resulting
in forming down flow F or oblique flow of the clean air.
In the second sub-system B, each of processing units SD1, SD2, HP1
to HP10 and CP4 of FIG. 4 corresponds to the "processing unit." The
processing units SD1 and SD2 in the first stage BF1 are disposed in
a row while the processing units HP7 to HP10 and CP4 in the second
stage AF2 are disposed in a row, so that a multi-stage multi-row
type processing is formed.
<A-4. Structure and Operation of Handler>
FIG. 6 is a diagrammatic perspective view of the handler 30a. Other
handlers 30b to 30f are identical in structure to the handler
30a.
The handler 30a comprises an arm 33 with two fingers 34a and 34b
which are secured on both ends thereof. The arm 33 is pivotally
mounted on a base 31 through a link 32 to rotate along the .theta.
direction with respect to the horizontal plane. When driven by a
motor (not shown) connected to the link 32, the arm 33 moves
forwardly and backwardly. The arm 33 can also go up and down. Thus,
the handler 30a is a R-.theta.-Z robot and can transfer the
substrates without generating particles. The handler 30a moves
along guide rail 43 of FIG. 2. The handlers are connected to a
driving and controlling unit (not shown). Although the fingers 34a
and 34b are fitted on both ends of the linear arm 33 shown as being
180 degrees apart, an L-shaped member may be used as the arm 33,
for example. In this case where the L-shaped arm 33 is used, the
fingers 34a and 34b can be 90 or 60 degrees apart.
FIGS. 7A to 7C are schematic plan views showing the operation of
the handler 30a. The substrate 10a in processing unit 60 is removed
therefrom by handler 30a while another substrate 10b is delivered
to the same processing unit 60 by means of the handler 30a. The
processing unit 60 represents one of the aforementioned processing
units SS, SC, . . . .
Referring to FIG. 7A, the substrate 10b is held by the second
finger 34b while the substrate 10a is present in the processing
unit 60. The arm 33 is moved in the (+Y) direction with the second
finger 34b holding the substrate 10b and then takes the substrate
10a out of the processing unit 60 by using the first finger 34a and
moving arm 33 in the (-Y) direction.
Referring to FIG. 7B, the arm 33 is rotated until the second finger
34b faces the processing unit 60. Thereafter, the arm 33 is moved
in the (+Y) direction with the substrate 10b held by the second
finger 34b being inserted into the processing unit 60, as shown in
FIG. 7C.
It is understood from FIG. 7C that the substrate 10b is held by the
handler 30a. If the handler 30a moves to the next processing unit,
the above operation can be repeated. Thus, in the case where the
apparatus has a plurality of processing units, the substrates can
be sequentially transferred to each processing unit by using the
handler.
<A-5. Processing in the First Sub-system A>
Table 1 below shows a series of processing steps carried out in the
apparatus 1 of the embodiment. The respective processing steps,
listed in section "A" of Table 1, are carried out by the
corresponding processing units which are in column "APPARATUS".
TABLE 1 ______________________________________ TEMP. TIME SEC
PROCESSING APPARATUS (.degree.C.) (SEC.)
______________________________________ A SPIN SCRUBBING SS BAKE FOR
HP1 90 50 DEHYDRATION BAKE FOR HP2 90 50 DEHYDRATION COOLING CP1 30
50 BAKE FOR HP3 80 50 DEHYDRATION COOLING CP2 23 50 SPIN COATING SC
EDGE RICING ER PRE-BAKE HP4 100 50 PRE-BAKE HP5 100 50 PRE-BAKE RP6
100 50 COOLING CP3 23 50 EXPOSING ST B EDGE EXPOSING ET POSTBAKE
HP7 140 50 POSTBAKE HP8 140 50 POSTBAKE HP9 140 50 COOLING CP4 23
50 DEVELOPING SD1 100 (SD2)
______________________________________
In FIG. 8, a flow of the substrate is indicated by the arrows. The
flow will be now explained with reference to FIGS. 2 and 8 and
Table 1.
First, the substrate 10 is inserted into the spin scrubbing device
SS of the first stage AF1 by handler 30a. The substrate 10 that has
been subjected to the spin scrubbing treatment by the spin
scrubbing device SS is transferred to the elevator EL1 by the
handler 30a. Upon receiving the substrate 10, the elevator EL1 goes
up to the second stage AF2 with the substrate 10 being held
therein.
The substrate 10 is carried from the elevator EL1 by the handler
30c in the second stage AF2, and then transferred to the hot plates
HP1 and HP2 in that order, to be subjected to the heat processing
by the respective hot plates HP1 and HP2. Thereafter, the substrate
10 is transferred by the handler 30c to cool plate CP1 to be
subjected to the cooling processing.
The substrate 10 is transferred to the next hot plate HP3 and the
cool plate CP2 by the handler 30c. The heat processing may be
changed into the coating processing in which an
adhesion-strengthening agent for resist film is applied. A suitable
adhesion-strengthening agent is HMDS hexamethyldisilazane.
When the above process has been completed, the substrate 10 is
transferred to elevator EL1 by the handler 30c. Thereafter, the
elevator EL1 goes down to the first stage AF1 with the substrate 10
being held therein.
The substrate 10 is delivered by the handler 30b into the spin
coating device SC and the edge and back removing part ER
sequentially. The resist coating treatment is carried out in the
spin coating device SC, and thereafter the edge and back rinsing
treatment is carried out in the edge and back removing part ER.
Upon completion of the above treatments, the substrate 10 is
transferred to the elevator EL2 by the handler 30b. The elevator
EL2 goes up to the second stage AF2 with the substrate 10 being
held therein.
The substrate 10 is taken out of the elevator EL2 by means of the
handler 30d. For the purpose of conducting the preliminary bake
treatment, the substrate 10 is sent to the respective hot plates
HP4 to HP6 one after another, in that order, and then the substrate
10 that has been subjected to the preliminary bake treatment is
inserted into the cool plate CP3 to be subjected to the cool
processing. Thereafter, the substrate 10 is transferred to the
elevator EL2 by the handler 30d. The elevator EL2 goes down to the
first stage AF1 with the substrate 10 being held therein. The
substrate 10 is taken out of the elevator EL2, and then sent to the
buffer part 6 (in FIG. 1) by the handler 30b.
<A-6. Processing in Second Sub-system B>
Now referring to FIG. 9, wherein a flow of the substrate in the
second sub-system B is indicated by arrows. The series of
processing steps is described in section "B" of Table 1. The flow
will be now explained with reference to FIGS. 4 and 9 and Table
1.
The substrate 10, subjected to processing in the exposing machine 5
of FIG. 1 and the supplementary exposing part 7, is picked up by
the handler 30e to be transferred to the elevator EL3. The elevator
EL3 goes up to the second stage AF2, and then the substrate 10 is
transferred to the handler 30f which delivers the substrate 10 to
the hot plates HP7 to HP9 in that order.
It is understood from Table 1 that the postbake processing is
carried out for 50 seconds in the hot plate HP9. If the postbake
processing in the hot plate requires a processing time of more than
50 seconds, the odd substrate in the processing series may be
inserted into the hot plate HP9 while the even substrate in the
processing series may be inserted into the hot plate HP10 provided
on the upper layer.
The baked substrate 10 is inserted into the cool plate CP4 to be
cooled, and then transferred to the elevator EL4 by the handler
30e. The elevator EL4 goes down to the first stage BF1, so that the
substrate 10 in the elevator EL4 is delivered to the handler 30e
and the substrate 10 is transferred to the spin developing device
SD1 or SD2 by the handler 30e. Since the time required for
developing the resist film provided on the inserted substrate 10 is
100 seconds, the odd substrate in the processing series is inserted
into the first spin developing device SD1 while the even substrate
in the processing series is inserted into the second spin
developing device so that the total time required for spin
developing processing is constant.
The developed substrate 10 is taken out of the spin developing
device SD1 or SD2 and transferred to the unloading station 8 of
FIG. 1 by the handler 30e.
The series of operation is automatically controlled by means of the
cooperation between a control circuit and driving devices.
<A-7. Advantages of Substrate Processing Apparatus 1>
The substrate processing apparatus 1 having the above structure and
operation has the following advantages:
(a) Since the processing units are arranged in a multi-stage
configuration, the floor area for and the height of the apparatus 1
are reduced, facilitating set-up and operation for the apparatus
1.
(b) Since the handlers 30a to 30f can be approached easily from the
outside, the inspection and the maintenance for the apparatus are
facilitated.
(c) Since the plurality of processing units are arranged in a
matrix, the substrate can be taken into and out of the respective
processing units randomly.
For example, in the first sub-system A of the above embodiment,
strokes for movement of the respective handlers 30a to 30d are the
follows:
handler 30a; the stroke between the loading position for the
substrate 10 and the elevator EL1 in the first stage AF1,
handler 30b; the stroke between the elevators EL1 and EL2 in the
first stage AF1,
handler 30c; the stroke between the hot plate HP1 or HP2 and the
cool plate CP3 in the second stage AF2; and
handler 30d; the stroke between the hot plate HP6 and the elevator
EL2 or between the cool plate CP3 and the elevator EL2 in the
second stage AF2. These strokes scarcely overlap each other.
Although the strokes for the handlers 30a and 30b overlap at the
elevator EL1, the amount of overlapping is a negligible quantity
with respect to the size of the whole apparatus.
This allows handles 30a to 30d to move without interfering with
each other, in that movements of the handlers 30a to 30d can be
controlled individually. Accordingly, the process order for the
substrate 10 in the first sub-system A can be changed from the
above process order. For the same reason, the process order in the
second sub-system B can be changed, similarly.
(d) Since the floors 42 and 52 are provided in front of the
processing units, scattering of particles from one stage to another
stage is prevented.
(c) The corresponding down or oblique flows of the clean air for
the respective stages prevent particles from the transferring
mechanism from contaminating the substrate.
(f) In the apparatus 1, the handlers for transferring the substrate
are provided in each stage while the elevators for transferring the
substrate are provided therebetween. Accordingly, the substrates
can be moved in parallel and individually, to thereby improve
throughput.
<A-8. Modifications of First Embodiment>
(1) The first and second sub-systems may be arranged in a straight
line.
(2) The substrate may be transferred by means of a transferring
mechanism comprising a single transferring device which can
transfer the substrate in both horizontal and vertical directions
and which will be described the later, instead of by means of
individual devices for horizontal and vertical transfers.
(3) The plurality of processing units may be stacked in three or
more stages.
(4) The stages in the embodiment include the processing units in
either single or double layers. The stage may comprise three or
more layers thereof. The number of layers in each stage may be
optionally determined on the basis of the process and the heights
of the respective processing units. In the case where processing
units that are lower in height, such as hot plates, or cool plates
are provided, floor area can be saved by stacking such processing
units.
(5) It is particularly desirable for minimizing size of the whole
apparatus that the arrangement of the processing units is
determined so that the lengths of the first and second stages in
the X direction are identical to each other. However, the concept
of the present invention can be applied to apparatus in which the
length of the second stage in the X direction is shorter than that
of the first stage.
(6) The apparatus may optionally define whether or not the process
in the first stage has priority over the process in the second
stage. The number and arrangement of elevators may be changed as
found to be appropriate. Referring to FIG. 9, for example, the
elevator EL4 may be omitted and all the substrates may be
transferred between the first and second stages by means of the
elevator EL3.
(7) The elevator can function as a cool plate. More precisely, the
substrate may be cooled during the whole time it is on the
elevator.
(8) The kind of processing units may be defined on the basis of the
kind of substrate and process required.
(9) Although the processes in the respective processing units are
exemplified in Table 1, the former may be changed optionally. For
example, the heating time required in the hot plates HP4 to HP6 can
be different from that shown in Table 1. The next substrate may be
subjected to heat treatment by means of one hot plate not having
the substrate in place of heat treatment by means of the three hot
plates HP4 to HP6 in which the substrate is introduced in this
order.
(10) The present invention can be applied to the substrate
processing apparatus for processing substrates such as
semiconductor wafers or the like, as well as the apparatus for
processing the substrates of liquid crystal displays.
B. Device for and Method of Exchanging Substrate in Substrate
Processing Apparatus
<B-1. Overall Structure of Substrate Processing
Apparatus>
In connection with the arrangement illustrated in FIGS. 10 and 11,
substrate processing apparatus 1 acts as an apparatus for coating
photo-resist for use in forming patterns such as electrodes on a
surface of a liquid crystal display substrate.
In FIGS. 10 and 11 substrate processing apparatus 1 comprises a
sub-system A1 in which there are a plurality of processing units in
multi-stage arrangement. In the sub-system A1, the spin scrubbing
device SS, the spin coating device SC and the rinsing part ER are
disposed in the X direction, to thereby form a first stage AF1.
There is an interface part IF2, on which the substrate can be
introduced to the first stage.
A second stage AF2 is arranged above the first stage AF1. The
second stage AF2 has a two-layer structure, more precisely, a first
layer consisting of hot plates HP1, HP4, HP5 and cool plates CP1 to
CP3 which are arranged in the X direction; and a second layer
consisting of hot plates HP2, HP3 and HP6. As shown in FIG. 11, the
corresponding units in the first and second layers, for example the
cool plate CP3 and the hot plate HP6, are stacked. There is an
interface IF1, on which the substrate can be introduced to the
first layer. As described above, the apparatus 1 has the first
stage AF1 with the single layer and the second stage AF2 with the
two layers, so that a two stage and three layer structure is
formed.
There is a frame 200a in front of the processing part A1, i.e., in
the (-Y) side, the frame 200a expanding in the X direction. The
frame 200a is disposed at substantially center in height between a
pass line PS1 for taking the substrate in and out of the spin
coating device SC and a height level PL2 for taking the substrate
in and out of the upper processing unit HP6, as shown in FIG. 11.
Two parallel guide rails 201 and 202 extending in the X direction
are secured on the frame 200a with a predetermined distance in the
Z direction. A substrate transferring device 101 is connected to
the upper guide rail 201 to move along the guide rail 201 in the X
direction, although the connection between the substrate
transferring device 101 and the guide rail 201 is omitted in FIG.
10. Two substrate transferring devices 102 and 103 are connected to
the guide rail 202 to move along the guide rail 202 in the X
direction. These substrate transferring devices 101 to 103 transfer
the substrate among all of the processing units. The structure of
devices 101-103 will be more fully described later.
<B-2. Structure of Substrate Transferring Device>
Since the substrate transferring devices 101 to 103 in FIG. 11 are
identical in basic structure to each other, the following
description will now be focused on the structure of the substrate
transferring device 101.
<B-2-1. Whole Structure>
Referring to FIG. 13, the first substrate transferring device 101
is connected to the upper guide rail 201 secured on the frame 200a.
The substrate transferring device 101 comprises a X moving
mechanism 110 for moving the whole substrate transferring device in
the X direction. A vertical arm mechanism 120a, for stretching
(extending) and withdrawing in the vertical direction Z, is
connected to the X moving mechanism 110. The vertical arm mechanism
120a supports a hollow housing 131 which is open at each end
thereof as viewed in the Y direction. A horizonal arm mechanism
140, which can be stretched (extended) and withdrawn in the
horizontal direction Y, is fixed at a location within housing 131.
A pair of hands 150a and 150b are secured to the leading edge
portion of the horizontal arm mechanism 140.
<B-2-2. X Moving Mechanism 110>
Referring to FIG. 13 again, the X moving mechanism 110 comprises
rollers 111 and 112 sandwiching the guide rail 201 along the Z
direction. In the mechanism 110, a driving roller 113 is connected
to a motor 114 supported by a supporting member 115. Upon being
driven by the motor 114, the X moving mechanism 110 moves along the
guide rail 201, so that the substrate transferring device 101 is
moving in the X direction.
<B-2-3. Vertical Arm Mechanism 120a>
A motor 116 is fixed below the supporting member 115. The vertical
arm mechanism 120a comprises two arms 121a and 122a which are
substantially of the same length. One end portion of the arm 121a
is connected to the motor 116 while one end portion 123a of the arm
122a is connected to the housing 131. The vertical arm mechanism
120a is a scalar robot mechanism. Upon being driven by the motor
116, the arms 121a and 122a pivot as indicated by the arrows
.theta.1 and .theta.2, respectively, so that the housing 131 moves
along the Z direction in a predetermined path, as indicated by
arrow E1. When the rotary direction of the motor 116 is switched,
the moving direction of the housing 131 is reversed, more precisely
changed from the (+Z) direction into the (-Z) direction or from the
(-Z) direction into the (+Z) direction.
As shown in FIG. 14, the other vertical mechanism 120b, having a
construction identical to that of the vertical mechanism 120a, is
provided on the opposite side of the housing 131. These vertical
mechanisms 120a and 120b are connected to each other by a
connecting member 124 extending in the horizontal direction X.
Thus, the driving force of the motor 116 is transmitted to the
vertical arm mechanism 120b through the connecting member 124, the
result being that the arms in the vertical arm mechanism 120b pivot
at the same time that the respective arms in the vertical arm
mechanism 120a rotate, so that corresponding arms in the vertical
arm mechanisms 120a and 120b pivot to the same extent. Accordingly,
the housing 131 supported by the vertical arm mechanisms 120a and
120b moves in the Z direction in a predetermined position. A torque
spring 117 is provide in the vertical arm mechanism 120b for
balancing torque that is loaded by the motor 116 on the other
vertical arm mechanism 120a.
The substrate transferring device 102 shown in FIG. 13 is
substantially identical in structure to the substrate transferring
device 101. That is, devices 101 and 102 have the same construction
for the housings and internal elements, except that the X moving
mechanisms and the vertical arm mechanisms each have a construction
symmetrical with respect to the Z direction.
The respective housings provided in the substrate transferring
devices 101 to 103 can move from the pass line PS1 (see FIG. 11) to
the height level PL2 for taking the substrate in and out of the hot
plate HP6.
<B-2-4. Horizontal arm mechanism 140>
FIG. 14 is a plan view of the housing 131, with its upper or
ceiling surface cut away for the sake of clarity. One end portion
of the horizontal arm mechanism 140 is provided in and connected to
the housing 131. The horizontal arm mechanism 140 comprises two
arms 141 and 142 which are of substantially the same length. One
end portion 143 of the arm 141 is pivotally supported by the
housing 131 and connected to a motor 133 (see FIGS. 12 and 13). The
lead edge portion of the second arm 142 is connected to the hands
150a and 150b.
The horizontal arm mechanism 140 is also a scalar robot mechanism.
Upon being driven by the motor 133, the hands 150a and 150b move in
the (+Y) direction, to reach the processing unit. If the driving
shaft of the motor 133 reverses, the hands 150a and 150b move in
the (-Y) direction, to retract them for storage within the housing
131.
<B-2-5. Space controlling mechanism 160>
As shown in FIGS. 12 and 14, each of the hands 150a and 150b is a
plate with two fingers. The substrate is put on the hand 150a or
150b, and then transferred to the processing unit with the hands
150a and 150b being stored with the housing 131.
The hands 150a and 150b are connected to the lead edge portion of
the arm 142 by the space controlling mechanism 160. FIG. 16 is a
plan sectional view of the space controlling mechanism 160 taken in
the (-Z) direction. The space controlling mechanism 160 comprises a
body 161 having a through hole 168 which is connected to the lead
edge portion of the arm 142. The body 161 is provided with four
rails 163 that extend vertically. Two sliding blocks 162a and 162b
are slidably connected to the rails 163. The hands 150a and 150b
are fixed to the sliding blocks 162a and 162b respectively. An air
cylinder 166, which can be driven by compressed air, is attached to
the body 161 to drive a driving shaft 164 on which eccentric cams
165a and 165b are secured.
FIG. 17 is a front view of the space controlling mechanism 160
taken in the (+Y) direction, with portions broken away for the sake
of clarity. Guide through holes 167a and 167b, which have internal
side surfaces parallel to each other, are provided in the sliding
blocks 162a and 162b, respectively, to be guided by the movement of
the eccentric cams 165a and 165b. The pair of eccentric cams 165a
and 165b are eccentrically arranged in the opposite side across the
driving shaft 164. Thus, when the driving shaft 164 rotates, the
eccentric cams 165a and 165b push up the one of the sliding blocks
162a and 162b and push down the other. In other words, upon being
driven by the air cylinder 166, the hands 150a and 150b connected
to the sliding blocks 162a and 162b move in the Z direction, so
that the space between the hands 150a and 150b can be changed.
FIG. 18 is a detail view of portions connected between the arm 142
and the body 161, illustrating a sectional view of the attachment
mechanism 170 that is between the body 161 and the arm 142. The
attachment mechanism 170 comprises a hollow body 171 having a
recess in which a piston 172 is provided so as to slide along the
internal side surface thereof with an airtight condition. A pushing
member 173 is fitted to the piston 172. In the recess of the body
171, a compressed spring is stored to bias against the piston 172
and the pushing member 173 downwardly. The pushing member 173 is
inserted into the through hole 168 in the body 161 by the
downwardly biasing force, so that the body 161 and the arm 142 are
connected to each other. Hence, when compressed air is introduced
through an air transporting tube into an air room 176 formed by the
inner wall of the body 171 and piston 172, the piston 172 is pushed
up against the downwardly biasing force of the spring 174, so that
the pushing member 173 rises to the through hole 168. The pushing
member 173 rising in the through hole 168 permits member 173 to be
attached into and deattached out of the through hole 168 since a
notch is provided in the through hole 168 as shown in FIG. 16.
Accordingly, body 161 and the arm 142 are easily attached and
deattached by means of the attachment mechanism 170.
<B-3. Operation of Substrate Transferring Device>
FIGS. 19A to 19D are schematic diagrams showing the operations for
taking substrate 10 into and out of a processing unit 300, such as
a hot plate HP. Upper and lower substrate holding mechanisms 310a
and 310b are provided in the processing unit 300 so that the
substrate 10 is transferred between an exchange position for
exchanging a processed substrate for a next substrate and a
treatment position where the predetermined processing is carried
out. The space between the hands 150a and 150b can be controlled by
means of the air cylinder 166 in the space controlling mechanism
160. Thus, the space therebetween is controlled so as to be wider
or narrower than the space between the substrate holding mechanisms
310a and 310b.
A processed substrate 10a which has been processed by the
processing unit 300 is put on the upper substrate holding mechanism
310a. A next substrate 10b, which should be processed next by the
processing unit 300, is put on the lower hand 150b, the next
substrate 10b having been processed by other processing unit for
achieving the preliminary treatment prior to processing in the
specified processing unit 300. The substrate transferring device
101 in which the next substrate 10b is put on the lower hand 150b
moves in the X and Z directions, and then stops in front of the
processing unit 300, so that the lower hand 150b is positioned
vertically at the center between both of the substrate holding
mechanisms 310a and 310b. During the above movement, the hands 150a
and 150b are stored within the housing 131 while the space
therebetween is narrower than the space between both of the
substrate holding mechanisms 310a and 310b (this is a "narrow
state").
Next, the horizontal arm mechanism 140 is stretched in the (+Y)
direction so that the hands 150a and 150b are inserted into the
processing unit 300 till the hands 150a and 150b reach the position
between the substrate holding mechanisms 310a and 310b. At this
time, the upper hand 150a is located under the processed substrate
10a while the lower substrate holding mechanism 310b is located
under the next substrate 10b, as shown in FIG. 19B.
Thereafter, the space controlling mechanism 170 is operated, so
that the hands 150a and 150b go up and down respectively (this is a
"wide state"), and then stop when the hands 150a and 150b pass
through the substrate holding mechanisms 310a and 310b,
respectively (FIG. 19C). By means of the movement of the hands 150a
and 150b, the processed substrate 10a is picked up by the upper
hand 150a while the next substrate 10b is put on the lower
substrate holding mechanism 310b. In other words, the processed
substrate 10a is transferred from the upper substrate holding
mechanism 310a to the upper hand 150a while the next substrate 10b
is transferred from the lower hand 150b to the lower substrate
holding mechanism 310b.
Next, the horizontal arm mechanism 140 is withdrawn in the (-Y)
direction so that the hands 150a and 150b are stored within the
housing 131, as shown in FIG. 19D. Then, the substrate transferring
device 101 moves in the X and Z direction to transfer the processed
substrate 10a to other processing unit in which the substrate 10a
will be subjected to further processing. The next substrate 10b
introduced into the processing unit 300 is transferred to the
predetermined position in the processing unit 300 where the
substrate is subjected to processing.
From FIGS. 20A to 20D, it is understood that positional
relationship between the substrates 10a and 10b can be reversed. In
this case, the processed substrate 10a, which must be taken out of
the processing unit 300, is put on the lower substrate holding
mechanism 310b while the next substrate 10b, which must be taken
therein, is put on the upper hand 150a. The substrate transferring
device 101 is brought to a position in front of the processing unit
300 in wide state (FIG. 20A). After stretching the horizontal arm
mechanism 140 in the (+Y) direction to insert the hands 150a and
150b into the processing unit 300 (FIG. 20B), the respective hands
150a and 150b go down and up respectively to be in narrow state
(FIG. 20C). By means of the movement of the hands 150a and 150b,
the processed substrate 10a is picked up by the lower hand 150b
while the next substrate 10b is put on the upper substrate holding
mechanism 310a. In other words, the processed substrate 10a is
transferred from the lower substrate holding mechanism 310b to the
lower hand 150b while the next substrate 10b is transferred from
the upper hand 150a to the upper substrate holding mechanism 310a.
Upon completion of exchanging the processed substrate 10a for the
next substrate 10b, the horizontal arm mechanism 140 is withdrawn
in the (-Y) direction so that the hands 150a and 150b are stored
within the housing 131 (FIG. 20D).
In the case where the substrate processing apparatus 1 comprises
various kinds of processing units 300, the substrate 10 is
transferred along the arrangement of the processing units 300 and
is taken in and out of the processing unit 300 in predetermined
order, so that a series of processing steps is carried out. The
relationship in the vertical direction between the processed
substrate 10a and the next substrate 10b may be changed according
to the number of processing units 300 required for processing a
substrate in the series. In more detail, the processed substrate
10a stored with the processing unit 300 in FIG. 19A may be
transferred to the next processing unit 300 in FIG. 20A as the
substrate 10b to be processed therein, and the processed substrate
10a stored within the processing unit 300 in FIG. 20A may be
transferred to the next processing unit 300 as the next substrate
10b to be processed therein. This allows the substrate to be
transferred directly from one processing unit to the next
processing unit without transferring the substrate 10a or 10b
between the hands 150a and 150b. Accordingly, the substrate can be
transferred with high efficiency.
<B-4. Structure and Operation of Substrate Holding Mechanisms
310a and 310b >
The structure and operation of the substrate holding mechanisms
310a and 310b in the processing unit 300 will now be described with
particular reference to FIG. 21.
<B-4-1. Spin Coating Device>
The substrate holding mechanisms 310a and 310b in the spin coating
device SC of FIG. 21 comprise four pins 320 each of which has upper
and lower claws. The pins 320 are pivotally fitted to nozzles 321.
The pins 320 are adapted to be driven through a belt 322 so as to
swing horizontally. When the pins 320 are positioned in closed
state, as indicated by solid line in FIG. 21, the substrate 10 is
supported by one of the claws.
Each of the nozzles 321 has a spray hole 323 for spaying rinsing
liquid toward the edge portions of the substrate 10 held by the
pins 320, the spay hole 323 extends horizontally along a side of
the substrate 10. Horizontal arm mechanisms 325 connect between
bases 324 and the nozzles 321, and adjust the space between the
nozzles 321 as a function of the size of the substrate 10. There is
a rotary table 326 that is rotatable in a horizontal plane and is
movable vertically. The rotary table 326 is connected to suction
means (not shown) to apply suction to the bottom surface of the
substrate 10, so that the substrate 10 is held on the rotary table
326. A nozzle 328 for spraying treating liquid, such as resist
liquid, toward the substrate 10 is disposed between the pins 320
and top edge portions of a cup 327 located under the pins 320. The
nozzle for treating liquid 328 is pivotable horizontally about a
pivot axis 329.
The operation of the spin coating device SC will be now explained,
assuming that the processed substrate 10a is put on the upper claws
of the pins 320 and the next substrate 10b is put on the lower
claws thereof. The next substrate 10b to be processed in the device
SC is transferred from the substrate transferring device 101 onto
the claws of the pins 320. During the transferring of the next
substrate 10b, the rotary table 326 elevates upwardly from the
position lower than the pins 320 to the upper position so that the
substrate 10b rises to the surface of the lower claws. Thus, the
substrate 10b is applied to suction and held by means of the rotary
table 326. Thereafter, the pins 320 pivot in an opening direction
OD, and then the substrate 10b is lowered while being held by the
rotary table 326, so as to being located in the cup 327. During
substrate locating, the nozzle for treating liquid 328 is located
at the retracted or shunting position as indicated by dashed line
in FIG. 21 in order not to interface with the substrate 10b.
Next, the nozzle 328 pivots until the lead edge portion thereof is
located above the center of the rotary table 326. The rotary table
326 rotates in a horizontal plane after the resist liquid has been
sprayed, so that the upper surface of the substrate 10b is coated
with the resist liquid. The cup 327 recovers excess resist liquid
and prevents same from scattering. Upon completion of coating, the
rotary table 326 stops rotating, and then the nozzle for treating
liquid 328 rotates to the shunting position.
The substrate 10a subjected to the above spin coating treatment is
lifted by means of rotary table 326 so as to rise to the surface of
the upper claws of the pins 320. Following that, the pins 320 pivot
in the closing direction CD while the rotary table 326 is lowered
to the position slightly lower than the pins 320. Thus, the
substrate 10a is transferred from the rotary table 326 onto the
upper claws of the pins 320.
Then, the hands 150a and 150b (FIG. 12) move to the position at
which the processed substrate 10a is located, and exchange the
processed substrate 10a for the next substrate 10b to be processed
in the spin coating device SC. The next substrate 10b transferred
to the lower claws of the pins 320 is put on the rotary table 326
by elevating the rotary table 326. The spin coating device SC then
repeats the above processing.
The substrate holding mechanism described above can also be applied
to devices such as a spin scrubbing device and a spin developing
device.
<B-4-2. Hot Plate HP>
The substrate holding mechanisms 310a and 310b in the hot plate HP
will now be described with particular reference to FIG. 22. The
upper substrate holding mechanism 310a comprises four upper levers
330 while the lower substrate holding mechanism 310b comprises four
lower levers 331. Each of the levers 330 and 331 includes a claw in
the form of a round bar. The levers 330 and 331 are pivotally
mounted to a heater 332. A sub-plate 333 which receives the
substrate 10 directly, is located above the heater 332. The hot
plate HP includes a front panel 334 having a window 335 through
which the substrate transferring device 101 inserts substrates into
the hot plate HP. There is a plate 336 supported by an elevator 338
above the upper and lower levers 330 and 331. Thus, upon being
driven by an air cylinder 337 provided in the elevator 338, the
plate 336 goes up and down.
Now referring to FIG. 23 for viewing the insides of the hot plate
HP each of the upper and lower levers 330 and 331 is biased by a
spring 339 so that the claw upwardly stands up. Stoppers 340 limit
pivoting of the levers 330 and 331 under the influence of the
spring bias force, to locate the levers 330 and 311 at the
predetermined positions shown. In this stopped state, the claws of
the upper levers 330 are positioned at the position higher than the
claws of the lower levers 331. As the plate 336 goes down, a pad
341 fixed on the bottom surface of the plate 336 contacts the top
portions of the upper levers 330 and pushes the upper lever 330
down, and also contacts the top portions of the lower levers 331
and pushes the lower lever 331 down. Trenches 342 (FIG. 22) are
provided to the side surface of the sub-plate 333 so that the claws
of the upper and lower levers 330 and 331 are shunted to the
trenches 342 when the plate 336 goes down.
Link mechanism 350 (FIG. 24) connects between the upper levers 330.
More particularly, upper levers 330 are connected to each other
through splines 351 and link plates 352 so that the pivot points
coincide with each other. The side width or distance between a pair
of the upper levers 330 which are connected to each other through
the spline 351 can be varied by the action of the air cylinder
353.
In FIG. 25 respective substrates 10a and 10b are seen supported on
the claws of the corresponding upper and lower levers 330 and 331.
The substrate holding mechanism described above can also be applied
to a cool plate CP or the like.
<B-4-3. First Operation of Hot Plate HP>
FIG. 26 is a timing chart illustrating the first operation of the
substrate transferring device 101 and the hot plate HP, assuming
that the processed substrate 10a is put on the claws on the upper
levers 330 while the next substrate 10b should be put on the claws
of the lower levers 331.
Initially, the processed substrate 10a is put on the claws of the
upper levers 330 while the plate 336 is located at the upper
position. The substrate transferring device 101 is brought to a
position in front of the hot plate HP with the lower hand 150b
thereof holding the next substrate 10b to be processed in the hot
plate HP. The horizontal arm mechanism 140 is withdrawn while the
hands 150a and 150b are in the narrow state.
The hands 150a and 150b are inserted into the hot plate HP through
the window 335 by stretching the horizontal arm mechanism 140. The
upper hand 150a reaches the position under the processed substrate
10a in the hot plate and the next substrate 10b on the hands 150b
is raised to the position above the claws of the lower levers 331
(time t1 to time t2).
The space between the hands 150a and 150b increases by operating
the space controlling mechanism 170, whereby the processed
substrate 10a is transferred from the claws of the upper levers 330
to the upper hand 150a while the next substrate 10b to be processed
is transferred from the lower hand 150b to the claws of the lower
lever 331 (time t2 to time t3). Thus, the exchange of the processed
substrate 10a for the next substrate is completed. Next, the
horizontal arm mechanism 140 is withdrawn with the space between
the hands 150a and 150b being in the wide state, to store the
processed substrate 10a within the housing 131. At the same time,
the air cylinder 353 acts to expand the side width wide between the
upper lever 330 (time t3 to t4).
The plate 336 comes down, to thereby lower the lower levers 331
supporting the next substrate 10b, so that the next substrate 10b
is put on the upper surface of the sub-plate 333 (time t4 to time
t5). Although the upper levers 330 are also pushed down by the
plate 336 during the above operation, the increase in the side
width between the upper levers 330 prevents interference with the
substrate 10b. After time t4, the substrate 10a is transferred to
another processing unit by means of the substrate transferring
device 101, to carry out the next process.
After time t5, heat processing for the substrate 10b is carried out
on the sub-plate 333 (time t5 to time t6). Upon completion of heat
processing, the space between the upper levers 330 is narrowed
(time t6 to time t7), and then the plate 336 rises (time t7 to time
t8). As the plate 336 goes up, the upper and lower levers 330 and
331 rise gradually. Since the side width between the upper levers
330 is narrow, the processed substrate 10a subjected to the above
heat processing is put on the claws of the upper levers 330 and
goes up. After the plate 336 rises fully, exchange of the processed
substrate 10a for the next substrate 10b is carried out. In other
words, after time t8, the operation similar to that from time t1 to
time t8 is repeated.
<B-4-4. Second Operation of Hot Plate HP>
FIG. 27 is a timing chart illustrating the second operation of the
substrate transferring device 101 and the hot plate HP, assuming
that the processed substrate 10a is put on the claws of the lower
levers 331 while the next substrate 10b is put on the claws of the
upper levers 330, in reverse.
Initially, the processed substrate 10a is put on the claws of the
lower levers 331 while the plate 336 is located at the upper
position. The substrate transferring device 101 is brought to a
position in front of the hot plate HP with the upper hand 150a
thereof holding the substrate 10b to be processed in the hot plate
HP. The horizontal arm mechanism 140 is withdrawn while the hands
150a and 150b are in the wide state.
The hands 150a and 150b are inserted into hot plate HP through the
window 335 by stretching the horizontal arm mechanism 140 until the
lower hand 150b reaches the position under the processed substrate
10a in the hot plates and the next substrate 10b put on the hand
150a reaches the position above the claws of the upper levers 330
(time t1 to time t2). At the same time, the side width of the upper
levers 330 is narrowed.
The space between the hands 150a and 150b is narrowed by actuating
the space controlling mechanism 170, whereby the processed
substrate 10a is transferred from the claws of the lower levers 331
to the lower hand 150a while the next substrate 10b to be processed
is transferred from the upper hand 150b to the claws of the lower
lever 331 (time t2 to time t3). Thus, exchange of the processed
substrate 10a for the next substrate is completed. Next, the
horizontal arm mechanism 140 is withdrawn with the space between
the hands 150a and 150b being in the narrow state, to store the
processed substrate 10a with the housing 131.
The plate 336 comes down, to thereby push down the upper levers 330
supporting the substrate 10b, the result being that substrate 10b
is put on the upper surface of the sub-plate 333 (time t4 to time
t5). Since the lower levers 331 are pushed down at the same time,
there is no interference with the substrate 10b. After time t4, the
substrate 10a is transferred by the substrate transferring device
101 to another processing unit to carry out the next process.
After time t5, heat processing for the substrate 10b is carried out
on the sub-plate 333 (time t5 to time t6). Upon completion of heat
processing, the space between the lower levers 331 is expanded
(time t6 to time t7), and then the plate 336 rises (time t7 to time
t8). As the plate 336 goes up, the upper and lower levers 330 and
331 rises gradually. Since the side width between the upper levers
330 is wide, the processed substrate 10a subjected to the above
heat processing is placed on the claws of the lower levers 331 and
rises. After the plate 336 rises fully, exchange of the processed
substrate 10a for the next substrate 10b is carried out between the
substrate transferring device 101 and the hot plate HP. In other
words, after time t8, the operation similar to that from time t1 to
time t8.
<B-5. Efficiency of Processing>
The efficiency of the processing in the substrate processing
apparatus 1 described above will now be explained with reference to
Table 2 which shows a series of processing steps carried out in the
apparatus 1.
TABLE 2
__________________________________________________________________________
PROCESSING TEMP. TIME TRANSFERRING PROCESSING PART .degree.(C.)
(SEC.) DEVICE
__________________________________________________________________________
SPIN SCRUBBING SS 101 BAKE FOR HP1 90 50 DEHYDRATION BAKE FOR HP2
90 50 DEHYDRATION COOLING CP1 30 50 BAKE FOR HP3 80 50 102
DEHYDRATION COOLING CP2 23 50 SPIN COATING SC EDGE RINSING ER
PRELIMINARY BAKE HP4 100 50 103 PRELIMINARY BAKE HP5 100 50
PRELIMINARY BAKE HP6 100 50 COOLING CP3 23 50
__________________________________________________________________________
It is understood from Table 2 that a total time T for the series of
processing steps is 50 seconds. Now if an average time required for
transferring the substrate from one processing unit to other
processing unit and for taking the substrate in and out of the
processing unit by each of the substrate transferring devices 101
to 103 is .DELTA.T, and the number of processing units required in
one substrate processing apparatus being N, the following
relationship holds.
The reason why the expression (1) includes a term "(N+1)" is
because it is necessary for the substrate transferring device to
take the substrate in and out of the processing unit (N-1) times
while moving among N processing units and that the substrate
transferring device takes the substrate in and out of other
processing units before and after the above movement. In the case
where the average time of .DELTA.T is 10 seconds, for example, the
following expression (2) is given from the expression (1).
Hence, N.ltoreq.4, the maximum value becomes "4". The series of
processing steps listed in Table 2 may be divided by four units.
The substrate transferring device 101 takes a substrate from the
spin scrubbing device SS to the cool plate CP1, the substrate
transferring device 102 takes a substrate from the hot plate HP3
for dehydration bake to the edge and back rinsing part ER, and the
substrate transferring device 103 takes a substrate from the hot
plate HP4 for preliminary bake to the cool plate CP3. In Table 2,
parts corresponding to the respective substrate transferring
devices 101 to 103 are listed in section "TRANSFERRING DEVICE", are
indicated by symbols "101", "102" and "103". That is, the
respective substrate transferring devices 101 to 103 transfer the
substrate only among the corresponding parts.
The substrate transfer between the first and second substrate
transferring devices 101 and 102 is carried out through the
interface IF1 (see FIG. 10). For example, the substrate subjected
to processing in the cool plate CP1 is transferred onto the
interface IF1 through the substrate transferring device 101 and
then picked up by the substrate transferring device 102.
The average time .DELTA.T is a time required for exchanging a
substrate for the substrate held in the substrate holding mechanism
of the processing unit and then transferring the substrate to the
next processing unit. Since each of the substrate transferring
devices 101 to 103 can not only take the next substrate in but also
takes the processed substrate out of the processing unit at the
same time, the process and the substrate exchange in each
processing units can be terminated until the average time .DELTA.T
has passed. If the substrate transferring device can carry out only
taking the substrate in or out of the processing unit at one time,
such substrate transferring device must move without holding the
substrate. Thus, such substrate transferring device can barely
charge about N/2 of processing units. On the other hand, the
substrate transferring devices 101 to 103 having the hands 150a and
150b can exchange the processed substrate for the next substrate in
cooperation with the substrate holding mechanisms 310a and 310b.
Thus, using devices 101 to 103, the substrate can be transferred at
high efficiency.
In the substrate transferring devices 101 to 103, the processed
substrate can be exchanged for the next substrate by means of
controlling the space between the hands 150a and 150b, resulting in
that the time required for exchanging the processed substrate for
the next substrate is shortened. This allows the efficiency of
transferring the substrate to raise. Furthermore, the shortening of
the time for exchange of the processed substrate for the next
substrate allows the average time .DELTA.T to shorten. Accordingly,
the number of processing units which are serviced by one substrate
transferring device increases, as understood from the expression
(1). From a different point of view, the number of substrate
transferring devices to be provided in the substrate processing
apparatus 1 decreases.
In each of the processing units, the two substrate holding
mechanisms are arranged in a stack and the substrate moves between
the substrate holding mechanism and the position where the
processing for the substrate is carried out. Accordingly, the time
required for exchange of the processed substrate for the next
substrate is slight with respect to the total time T.
According to the substrate processing apparatus 1, the substrate
processing is achieved at high efficiency by means of the substrate
transferring device.
<B-6. Modification>
(1) FIG. 28 illustrates a modified construction of plate 336 and
upper lever 330 in the hot plate HP. In the modification of FIG.
28, the pad 341 is a permanent magnet and permanent magnet 343 is
fixed on the top of the upper lever 330 so as to face to the pad
341. The surfaces of the pad 341 and the magnet 343, which face to
each other, have the same magnetic polarity. Thus, as the plate 336
goes down, the magnetic resiliency increases and pushes down the
upper lever 330 without contact to the pad 341. The lower lever 331
facing the pad 341 is identical in structure and operation to upper
lever 330 and magnet 343 thereon. With this modified construction
the operative engagement between plate 336 and levers 330, 331 does
not result in particles being generated.
(2) FIG. 29 illustrates a modification of the upper hand 150a.
Although the upper hand 150a of FIG. 12 has the two claws made from
the plate, each of the claws may, as in FIG. 29, be made from a bar
having a C-shape in section. Stoppers 401 may be provided at the
lead edge portions of each claw in order to prevent the substrate
from dropping out of the hand 150a and from displacement. The lower
hand 150b may be structured similar to the upper hand 150a. The
claw may have a H-shape, an I-shape or the like in section instead
of the C-shape in section. The lightweight claws are shaped in
section so that they can support a heavy substrate without
deformation thereof.
(3) In order to generate the rotary force, an electrical motor may
be used instead of the air cylinder 166. The air cylinder 166
excels because it generates high torque with small size and can be
positioned between the upper and lower hands 150a and 150b.
(4) Although the processes in the respective processing units are
exemplified in Table 2, they may be changed optionally. For
example, the heating time required in the hot plates HP4 to HP6 can
be different from that shown in Table 2. The next substrate may be
subjected to heat treatment by means of one hot plate not having
the substrate in place of heat treatment by means of the three hot
plates HP4 to HP6 to which the substrate is introduced in this
order.
(5) The number of arms in the arm mechanism on the substrate
transferring device is not limited. The vertical arm mechanism may
be arranged on the horizontal arm mechanism. Since in this case the
connecting part between the vertical arm mechanism and the hands
must be long, the embodiment described above is of advantage.
(6) The present invention can be applied to the substrate
processing apparatus for processing substrates such as
semiconductor wafers or the like as well as the apparatus for
processing the substrates of liquid crystal display.
While the invention has been shown and described in detail, the
foregoing description is in all aspects illustrative and not
restrictive. It is therefore understood that numerous modifications
and variations can be devised without departing from the scope of
the invention.
* * * * *